Measuring PROMIS® Physical Activity and Sleep Problems in Early Childhood.

Objective: Physical activity (PA) and sleep are leading health indicators for individuals of all ages. Monitoring young children's PA and sleep using psychometrically sound instruments could help facilitate timely interventions to promote healthy development. This article describes the development of the PROMIS® Early Childhood (EC) Parent Report Physical Activity (PA) and Sleep Problems (SP) measures for children aged 1-5 years.

Methods: Item pools were generated by interviewing parents, input from content experts, and literature review. Data from a U.S. general population sample were used to determine factor structures of item pools via factor analytic approaches, estimate item parameters via item response theory (IRT) models, and establish norms. Pearson correlations were used to evaluate across-domain associations. Analysis of variance was used and known-groups' validity of PA and SP by comparing their scores to PROMIS EC Parent Report Global Health: child's physical, emotional, and mental conditions.

Results: Initial item pools consisted of 19 and 26 items for PA and SP, respectively. Factor analyses' results supported unidimensionality of 5 and 16 items measuring PA and SP, respectively, which were then calibrated using IRT. Norms were established by centering to a probability-based U.S. general population. Computerized adaptive testing algorithms were established. Some analyses supported initial measure validity.

Conclusions: The PROMIS EC PA calibrated scale and SP item banks are user-friendly and brief, yet produce precise scores. Both measures enable psychometrically sound assessment of PA behavior and sleep problems. Future studies to comprehensively evaluate the validity of these two measures are warranted.